# CVE-2026-68257: drm/amdkfd: fix 32-bit overflow in CWSR total size calculation

> A 32-bit integer overflow in the Linux kernel's AMD KFD driver allows undersized memory allocations, potentially leading to buffer overruns and code execution.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-68257, DEBIAN-CVE-2026-68257, GHSA-rqrw-7v4f-gfw3, UBUNTU-CVE-2026-68257

## What is CVE-2026-68257?

CVE-2026-68257 is a high-severity vulnerability in Linux, published on 10 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

drm/amdkfd: fix 32-bit overflow in CWSR total size calculation

total_cwsr_size was computed in 32-bit before being used as a BO/SVM
allocation size.
With large ctx_save_restore_area_size and debug_memory_size
multiplied by the XCC count, the product can wrap,
yielding an undersized CWSR save area that firmware later overruns.

Promote total_cwsr_size to u64 and use check_add_overflow()/
check_mul_overflow() in both kfd_queue_acquire_buffers() and
kfd_queue_release_buffers().

(cherry picked from commit 319f7e13423ae3f486b9aea82f9ad2d6af0ee608)

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2026-68257?


## How do I fix CVE-2026-68257?

Apply the vendor's patch.

## Is CVE-2026-68257 being exploited?

There is no known exploitation of CVE-2026-68257 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68257 and fix it if it is affected.

What it is: CVE-2026-68257 is a high-severity vulnerability in Linux, published on 10 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-68257 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-68257/ (Markdown: https://insights.sbomify.com/CVE-2026-68257/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68257
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68257
- OSV: https://osv.dev/vulnerability/CVE-2026-68257

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68257/
Summaries are generated and may contain mistakes; the official description above is the record.